Department of Department of Bone and Joint, Affiliated Hospital of Southwest Medical University, 646000, Luzhou, People's Republic of China.
BMC Musculoskelet Disord. 2021 Aug 27;22(1):734. doi: 10.1186/s12891-021-04617-7.
The repair of large bone defects is a great challenge for orthopedics. Although the development of three-dimensional (3D) printed titanium alloy (Ti6Al4V) implants with optimized the pore structure have effectively promoted the osseointegration. However, due to the biological inertia of Ti6Al4Vsurface and the neglect of angiogenesis, some patients still suffer from postoperative complications such as dislocation or loosening of the prosthesis.
The purpose of this study was to construct 3D printed porous Ti6Al4V scaffolds filled with bone marrow mesenchymal stem cells (BMSC) and endothelial progenitor cells (EPC) loaded hydrogel and evaluate the efficacy of this composite implants on osteogenesis and angiogenesis, thus promoting osseointegration.
The porosity and pore size of prepared 3D printed porous Ti6Al4V scaffolds were 69.2 ± 0.9 % and 593.4 ± 16.9 μm, respectively, which parameters were beneficial to bone ingrowth and blood vessel formation. The BMSC and EPC filled into the pores of the scaffolds after being encapsulated by hydrogels can maintain high viability. As a cell containing composite implant, BMSC and EPC loaded hydrogel incorporated into 3D printed porous Ti6Al4V scaffolds enhancing osteogenesis and angiogenesis to repair bone defects efficiently. At the transcriptional level, the composite implant up-regulated the expression levels of the osteogenesis-related genes alkaline phosphatase (ALP) and osteocalcin (OCN), and angiogenesis-related genes hypoxia-inducible factor 1 alpha (HIF-1α), and vascular endothelial growth factor (VEGF).
Overall, the strategy of loading porous Ti6Al4V scaffolds to incorporate cells is a promising treatment for improving osseointegration.
骨科领域一大挑战在于修复大的骨缺损。尽管开发出优化了孔隙结构的三维（3D）打印钛合金（Ti6Al4V）植入物可有效促进骨整合，但由于 Ti6Al4V 表面的生物惰性和对血管生成的忽视，一些患者仍会遭受术后并发症，如假体脱位或松动。
本研究旨在构建 3D 打印多孔 Ti6Al4V 支架，填充骨髓间充质干细胞（BMSC）和内皮祖细胞（EPC）负载水凝胶，并评估这种复合植入物在成骨和血管生成方面的功效，从而促进骨整合。
所制备的 3D 打印多孔 Ti6Al4V 支架的孔隙率和孔径分别为 69.2±0.9%和 593.4±16.9μm，这两个参数有利于骨长入和血管形成。水凝胶包封后填充到支架孔隙中的 BMSC 和 EPC 仍保持高活力。作为一种细胞复合植入物，BMSC 和 EPC 负载水凝胶与 3D 打印多孔 Ti6Al4V 支架结合，可有效促进成骨和血管生成，修复骨缺损。在转录水平上，复合植入物上调了成骨相关基因碱性磷酸酶（ALP）和骨钙素（OCN），以及血管生成相关基因缺氧诱导因子 1 ɑ（HIF-1ɑ）和血管内皮生长因子（VEGF）的表达水平。
总的来说，负载多孔 Ti6Al4V 支架以整合细胞的策略是一种很有前途的改善骨整合的治疗方法。
